Apple has suggested a temporary workaround to address it. In the support document, Apple describes the symptoms as follows:

â€œIn some regions, shortly before or after the daylight saving time (DST) change, repeating alarms created in the Clock app may work incorrectlyâ€

Apple has provided the following workaround to resolve the issue, which incidentally was suggested by some of our readers (thanks everyone):

To resolve this behavior for existing alarms, set the repeat interval to Never. You will need to reset these alarms for each day you need them.

According to the support document, you need to set the alarm manually for the next few days. After November 7th i.e. after the DST changes in US and Canada, you will be able to set your alarms to repeat again.